[FFmpeg-devel] [PATCH 2/2] avcodec/mjpegdec: add support for frame threading

Timo Rothenpieler timo at rothenpieler.org
Wed Dec 7 13:43:30 EET 2022


In my tests, this lead to a notable speed increase with the amount
of threads used. Decoding a 720p sample gave the following results:

1 Thread: 1428 FPS
2 Threads: 2501 FPS
8 Threads: 7575 FPS
Automatic: 11326 FPS (On a 16 Core/32 Threads system)
---
 libavcodec/jpeglsdec.c |  2 +-
 libavcodec/mjpegdec.c  | 11 ++++++-----
 libavcodec/sp5xdec.c   |  4 ++--
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/libavcodec/jpeglsdec.c b/libavcodec/jpeglsdec.c
index 2e6d018ea6..c0642e8e30 100644
--- a/libavcodec/jpeglsdec.c
+++ b/libavcodec/jpeglsdec.c
@@ -559,7 +559,7 @@ const FFCodec ff_jpegls_decoder = {
     .init           = ff_mjpeg_decode_init,
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP |
                       FF_CODEC_CAP_SETS_PKT_DTS,
 };
diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 9b7465abe7..54605e04cb 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -54,6 +54,7 @@
 #include "exif.h"
 #include "bytestream.h"
 #include "tiff_common.h"
+#include "thread.h"
 
 
 static int init_default_huffman_tables(MJpegDecodeContext *s)
@@ -713,7 +714,7 @@ int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
                 s->avctx->pix_fmt,
                 AV_PIX_FMT_NONE,
             };
-            s->hwaccel_pix_fmt = ff_get_format(s->avctx, pix_fmts);
+            s->hwaccel_pix_fmt = ff_thread_get_format(s->avctx, pix_fmts);
             if (s->hwaccel_pix_fmt < 0)
                 return AVERROR(EINVAL);
 
@@ -729,7 +730,7 @@ int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
         }
 
         av_frame_unref(s->picture_ptr);
-        if (ff_get_buffer(s->avctx, s->picture_ptr, AV_GET_BUFFER_FLAG_REF) < 0)
+        if (ff_thread_get_buffer(s->avctx, s->picture_ptr, AV_GET_BUFFER_FLAG_REF) < 0)
             return -1;
         s->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
         s->picture_ptr->key_frame = 1;
@@ -3020,7 +3021,7 @@ const FFCodec ff_mjpeg_decoder = {
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
     .flush          = decode_flush,
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .p.max_lowres   = 3,
     .p.priv_class   = &mjpegdec_class,
     .p.profiles     = NULL_IF_CONFIG_SMALL(ff_mjpeg_profiles),
@@ -3050,7 +3051,7 @@ const FFCodec ff_thp_decoder = {
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
     .flush          = decode_flush,
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .p.max_lowres   = 3,
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP |
                       FF_CODEC_CAP_SETS_PKT_DTS,
@@ -3068,7 +3069,7 @@ const FFCodec ff_smvjpeg_decoder = {
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
     .flush          = decode_flush,
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .caps_internal  = FF_CODEC_CAP_EXPORTS_CROPPING |
                       FF_CODEC_CAP_SETS_PKT_DTS | FF_CODEC_CAP_INIT_CLEANUP,
 };
diff --git a/libavcodec/sp5xdec.c b/libavcodec/sp5xdec.c
index 394448c5a9..8b08dc672a 100644
--- a/libavcodec/sp5xdec.c
+++ b/libavcodec/sp5xdec.c
@@ -101,7 +101,7 @@ const FFCodec ff_sp5x_decoder = {
     .init           = ff_mjpeg_decode_init,
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .p.max_lowres   = 3,
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP |
                       FF_CODEC_CAP_SETS_PKT_DTS,
@@ -118,7 +118,7 @@ const FFCodec ff_amv_decoder = {
     .close          = ff_mjpeg_decode_end,
     FF_CODEC_RECEIVE_FRAME_CB(ff_mjpeg_receive_frame),
     .p.max_lowres   = 3,
-    .p.capabilities = AV_CODEC_CAP_DR1,
+    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP |
                       FF_CODEC_CAP_SETS_PKT_DTS,
 };
-- 
2.34.1



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